3/16" Inch Cobalt Drill Bits - 13 Pack of M35 Cobalt Drill Bits with Storage Case - Perfect Drill Bits for Metal, Hardened & Stainless Steel, Cast Iron, and More!

Had to drill out seized bolts in rusted BBQ. Cobalt bits were hard enough too do the job in reasonable amount of time.

I was attempting to drill out some pretty stubborn screws on a derby cover on my Harley. The previous owner proceeded to strip out all five of the screws. I tried all the tricks to get them out including a rubber band, an easy out, etc. with no success. The metal was just too soft. This is why I replace these types of fasteners with new stainless steel.I purchased these drill bits because I was a sheet metal mechanic in the Air Force and I know that cobalt drill bits are what you need for harder types of metals. The heads on the screws were soft but the shank was not. After loading up my first cobalt bit and applying heavy pressure and slow speed, the bit ate right through the center of each screw. I went up two more sizes and ream out the hole. One more size jump and the head of each fastener popped off onto the drill bit just as I expected.

Real convenient for storage for often neededFor countersink bit

These drill bits cut through steel like butter.I had to do some modifications to my gazebo so it wasn’t moving in the windy weather days.Very happy.

I bought multiple bits knowing I'd wear out or lose a few considering the project. Nice and sharp getting a good bite when new. Dulled down relatively soon though and then they'd break. Not complaining this is to be expected soon when using such a small bit. I was doing pilot holes in galvanized sheet metal. Imo, excellent value for the money spent.

didn't read description fully. Thought they were jobber length

Went through 1/4 steel with no problems.

Cuts cleanly.

Al abrir el paquete me encontré con esa sorpresa, una broca quebrada y con señas de que fue usada, en la descripción del producto se menciona que tiene garantía de por vida de (las brocas)